Depreciation methods. Mike Davis Enterprises purchased a delivery van for $40,000 in January 20X7. The van was estimated to have a service life of 5 years and a residual value of $6,000. The company is planning to drive the van 20,000 miles annually. Compute depreciation expense for 20X8 by using each of the following methods:
a. Units-of-output, assuming 17,000 miles were driven during 20X8
b. Straight-line
c. Double-declining-balance